[98.03] Kinematics of Globular Clusters from Tangential Velocities and Constraints on Formation Scenarios of the Galaxy

Tangential velocities of globular clusters derived from absolute
proper motions tied directly to galaxies allow one to determine
the orbit-type of the cluster, which contributes to a substantial
improvement for studies of cluster origins and destruction processes.
Also the full kinematics of globular clusters interpreted in combination
with metallicities, horizontal branch morphologies and ages, provide
strong constraints on formation scenarios of the Galaxy. We present
here results for fifteen southern globular clusters for which absolute
proper motions were determined with precisions between 0.4 and 1.0
mas yr^-1; this sample represents a third of the total number
of clusters which have absolute proper motions determinations.
To date, work in this field covers mostly inner (R_GC < 8 kpc),
metal-poor ([Fe/H]< -0.8) clusters. For these clusters,
our results together with previous work, show
significant overlap in metallicity for two kinematically distinct
populations: cold, rotationally-supported clusters, and hot,
pressure-supported ones. Also, our results indicate that, the most
metal-poor clusters ([Fe/H] < -1.8) in the inner parts of the Galaxy
are essentially a pressure-supported system with a large velocity
dispersion.
Other - more cluster-specific results - will also be discussed.

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